Upcoming (online) tournaments

1.Summer Global Open (finished)
(or Winter if you are in the southern hemisphere)

It’s an open tournament, so everyone can register, provided that they are available at the designated time.

Info: http://tinyurl.com/summerglobalopen
Register: https://goo.gl/forms/UoKpGQeo3wIhNz4Y2
Tournament room: http://tenhou.net/0/?C10350560
– Group A: 1:00 UTC June 10 (until ~5:00)
– Group B: 13:00 UTC June 10 (until ~17:00)
– Final: 16:00 UTC June 11 (until ~18:00)

The tournament has finished. Congratz to tateniu for their victory!

2.The Invitational

Planned time: July 1st

Same as last year’s Osamuko Invitational, some of the best players in the English-speaking community will be invited to participate in this tournament. More info (players and teams) would be updated later.

My Discord server. Common mistakes (3)

Recently, I opened a new Discord server, with the purpose of having more quality discussions about the competitive aspect of the game.  This is for people who want to improve and learn how to be as good as they can possibly be, and as such not recommended for people who just enjoy playing the game casually. If this channel caters to your interests, join us at: Competitive Riichi Hub

I should as well make it clear that I do not encourage dividing the current community in any way. The purpose here is only to create the best environment for players that want to get good, enabling them to get to a certain level as easily as possible. This Discord server is not associated with osamuko.com by any means.

Let’s go back to problem 3 at the previous Common mistakes (1) article.

 Tsumo:  (Dora unrelated)

I told you that is the correct choice here. Now, suppose you have this hand instead:

 Tsumo:  (Dora unrelated)

Here, discarding  is not always the best choice. In this case, if you want maximum speed, you should discard  instead, because after discarding 4p, 3p is an useful tile. If you discard 6p, 3p would be useless.

Common mistakes (3)


What would you do in this situation?

Most of you should already know about defense, but let’s admit it, no one could grasp all the theories about defense written in all those guides in one or two go, and I’m not an exception. A lot of you would discard  here because, well, it’s a reasonably safe tile and it does not destroy your hand’s development.

There’s a rule of thumb about defense that you need to remember: “When you are in 2-shanten or worse and facing a riichi, you have to defend in the safest way possible”. Except for desperate situations of course.

After discarding East here, you would still be in 2-shanten. Compare to an opponent who has already riichi’d, the chance for you to win against him is almost zero. And if you discard East, there’s still a chance that you would deal in. That’s why the correct choice must be , a 100% safe tile. Suppose in the next turn you don’t get a 100% safe tile, you should discard .

(This was in one of my matches back in 2014, and yeah, I discarded East back then too.) (more…)

Equipments for Tokujou

If you are a Tenhou player, you should have known that there are 4 different rooms for 4 different levels: Ippan, Joukyuu, Tokujou, Houou. Before getting to the main parts of this article, let’s see what those 4 levels are about – those descriptions are from the famous Riichi Book I, by Daina Chiba.

1. 一般 (ippan; lower-level room)
This is the only room where you can play initially. Games in this room can sometimes be a bit random, even chaotic at times. Some of the players in this room probably do not understand the rules very well. You very rarely come across strong players here.

2. 上級 (joukyuu; upper-level room)
You can play here if (1) your rank is 1 or higher or (2) you buy a two-month membership.
Games in the joukyu room are more reasonable than those in the lower-level room, but you still see many players who do not defend at all, do meaningless dama / unreasonable riichi, and make serious mistakes in maximizing tile efficiency.

In my impression, games at EMA tournaments most resemble games in the ippan and joukyuu rooms.

3. 特上 (tokujou; advanced room)
Requirements to play in this room are pretty demanding. You have to have a 四段 or higher rank and a 1800 or higher R. The latter requirement is particularly difficult to satisfy for intermediate players. As I wrote above, achieving the rank of 四段 is not that difficult, but satisfying the R ≥ 1800 condition requires that you take mahjong rather seriously. Since weak players are shut out from the tokujou room, games in tokujou are qualitatively different from those in the joukyu and ippan rooms. Games in this room feel similar to those you’d experience at regular mahjong parlors in Japan.

4. 鳳凰 (houou; phoenix room)
This is the highest-level room in Tenhou. In order to play in this room, you have to have all of the following: (1) a 七段 or higher rank, (2) a 2000 or higher R, and (3) a paid membership. Satisfying the first two conditions can be really, really challenging. This is arguably one of the highest-level mahjong locales in the whole world.


The article is mainly for Joukyuu players – my suggestion on what they could do to achieve Tokujou level. Including players that have reached Tokujou but drop back easily. (And yeah, there’d be article(s) about Tokujou players. Probably not as good as this one.)


An awesome video guide from the internet. Common mistakes (2)

First of all, I want to show you a really good video guide that was created recently. The author is DdR_Dan, a player from US, who is staying consistently at 6d on tenhou, even got 7d in the past. Although it’s a little long, in my opinion it’s one of the best guides out there for 1-3 dan players, or even 4-5. Be sure to check out this and other videos on his Youtube channel too!


Common mistakes (2)


A lot of inexperienced player would feel that  is an isolated tile from the  sequence and therefore, discard it. That is a crucial mistake.

 should be interpreted as  + , which are two ryanmens, and the good discard here should be . After that, if you draw 4m/7m to convert 56m into a sequence, or 5m/8m to convert 67m into a sequence, you’d get tenpai with ryanmen wait!

The number of tiles that would turn   into one sequence and one ryanmen is 22 (four 4m, three 7m, three 5m, four 8m, four 4s, four 6s). Meanwhile the number of tiles that would turn  into one sequence and one ryanmen is only 12 (four 7p, four 4s, four 6s).


In this case,  and  should not be discarded. In the same fashion as the previous example,  should be interpreted as  + , two ryanmens. You can either discard 7m or 6s here (there’s a small difference between them but it should not be discussed here).

Players should remember  and  shapes. Discard the “leftover” tile from those shapes is usually a bad mistake. (more…)

Common mistakes (1), plus my introduction

Hey there, I’m starfire, a.k.a amaika on tenhou.net. Some of you might have known me, some might not. I have played riichi since 2012. Now that I have become a decent player, 7d at the time posting this (even though I’m fully aware that I could drop back easily), and that the competitive part of the riichi community is not at a good state right now, I have decided to join the osamuko crew. My contents would definitely be not as good as xkime’s, but I hope that you readers can still find them useful! My posts will be written with the assumption that readers are familiar with the rules and common mahjong terms.

For my first post, I’d talk about some easily overlooked mistakes that are often committed by low-intermediate level players, including myself a lot of times.


 Tsumo: (Dora unrelated)

It is elementary mistake to discard  here.

New players only see pin tiles as  +  and  is leftover. However, in this case the pin tiles should be seen as  +  and  should be discarded, because your hand would now have Pinfu after 4p discard.

If you have something like , then the better discard choice would be , because you can’t have pinfu anyway, and two closed triplets give you more fu and the chance to kan. (more…)